[chiphead]

I've read here that stock thermostat in pontiacs was 180-195 depending on year. 210 isn't too hot, but it's on the boderline. 215 makes me real nervous, 220 I'm looking to pull over, at 225-230 you risk detonation/boilover and 230-above is gonna blow a headgasket or crack a head.

I had a P350 that used to run 200-220 all the time. It hit 230 once and blew the headgaskets. I put it back together and it ran, but the rings were hurt and it started to get weak and lose compression.

Tuning is very critical on these engines and it would take paragraphs to explain it all in one post. I'll condense in a nutshell:

12-14* base timing, 36* all in by 2800 RPM
You need a 4-core brass radiator minimum, 2-core aluminum better
Cast-iron impeller waterpump with good divider plate clearance
fan shroud, high-lift flex fan or 7-blade stock fan and HD clutch
160-180 high flow thermostat and good hoses. 16lb radiator cap and puke tank.
25% antifreeze if in warm climate, 40% in colder climates
verify carburetor is not lean anywhere in fuel map.
Verify sparkplug selection and heat range and gap.